Printing press feeder

ABSTRACT

A mechanism for feeding envelopes and the like one at a time to a printing press is disclosed. A guide rack feeds a stack of envelopes onto the top of a hollow drum which is rotationally oscillated by a cam drive. A vacuum is maintained inside the drum and small holes in the drum attract the envelopes by means of suction. With each oscillation an envelope is picked up and carried into a set of transfer rollers which convey the envelope into the printing press.

United States Patent Paulson [54] PRINTING PRESS FEEDER [72] Inventor: Harold'E. Paulson, 32 Island Road,

St. Paul, Minn. 55110 [22] Filed: Sept. 2, 1970 [21] Appl.No.: 68,819

[52] US. Cl ..271/29 [51] Int. Cl. ..B65h 3/10 [58] Field of Search ..271/29 [56] References Cited UNITED STATES PATENTS 2,770,458 11/1958 Halahan et al ..271/29 3,423,084 1/1969 Konazewski ..271/29 2,861,803 11/1958 Halahan et a1 ..271/29 3,291,482 12/1966 Stemmler ..271/29 X [is] 3,685,821 51 Aug. 22,1972

4/1961 Cunningham ..271/29 Primary Examiner -loseph Wegbreit Att0mey-Robert M. Dunning ABSTRACT A. mechanism for feeding envelopesand the like one at a time to aprinting press'is disclosed. A guide rack I feeds a stack of envelopes onto the top of a hollow drum which is rotationally oscillated by a cam drive. A vacuum is maintained inside the drum and small holes in the drum attract the envelopes by means of suction.

With each oscillation an envelope is picked up .and

carried into a set of transfer rollers which convey the p envelope into the printing press.

9 Claims, 8 Drawing Figures 8/1921 Weightman ..L27l/29 SHEET10F3 INVENTOR H HOLD 5 PAULSO/V ATTORNEY PATENTED M1922 Ian PATENTEIJ 15 sum 2 0F 5 INVENTOR' QQHAROLD 5., PAULSO/V BY M Brigg ATTORNEY PRINTING PRESS FEEDER BACKGROUND OF THE INVENTION In the prior art, a number of types of printing press feeders have been used but all of them have inherent difficulties which make them less than suitable. The best mechanisms operate to select stock from the bottom of a stack thus permitting large quantities of stock to be stacked in the feeder. One type of bottom-selecting feeder known in the art utilizes a pusher chain with small lugs on the chain which operate to engage individual envelopes or bits of stock and slide them into the printing press. However, the chains tend to wear out very quickly since they may not be lubricated due to the fact that oil or grease in the chain soils the envelopes or other stock that is being fed into the printing press. Another disadvantage of pusher chains is that they accept only rectangular stock having straight front and rear edges. Since the chains ride over a large number of sprockets they can not be easily moved to accept different sizes of envelopes and are thus severely limited as to the size envelopes they can handle. Also, chains tend to stretch after some use so that the lugs have to be continually readjusted to keep the envelopes entering the press at the correct intervals to achieve proper registration. Another type of prior art feeding device uses long swinging pickup arms with suction devices at the ends. However, the large swinging mass requires complex, expensive apparatus that wears out quickly. Also, this type of feeder often picks up envelopes improperly so they enter the press too early, too late, or crookedly so that improper registration results. The present invention avoids the above mentioned difficulties and provides a simple, reliable, very fast feeder mechanism for a printing press which is comparatively maintenance free.

SUMMARY OF THE INVENTION Briefly, the present invention operates to feed a stack of envelopes or other suitable stock by means of a guide rack onto the top surface of an oscillating cylindrical feed drum. The drum is hollow and connected to a vacuum source which sucks the envelopes into con-, tact with the oscillating drum through small holes in the surface of the drum. As the drum rotates away from the stack of envelopes it pulls the bottom most envelope with it and feeds that envelope between a pair of transfer rollers. The rollers direct the envelope into printing press. As the oscillating pickup vacuum feed drum rotates back underneath the stack of envelopes it sucks the next envelope against it on the rearward stroke thus sliding the envelope back firmly against the guide rack so that on the forward stroke perfect registration of the envelope is assured. On the next forward stroke the next envelope in the stack is fed into the roller system. The roller system comprises a pair of cylindrical drums, one on each side of the oscillating feed drum, which work in combination with small rubber wheels rolling thereon to accept the envelope from the vacuum feed drum. Since only the small vacuum pickup drum need be oscillated back and forth there is a minimum of moving mass and consequently a relatively small cam movement is all that is necessary to provide the oscillating motion. Since there is a minimum of moving parts wear is reduced to a minimum and since there are no elaborate pusher chains involved it is not necessary to provide return space in which to bring the chain back to its starting point. The present invention is therefore much more compact than the apparatus utilized in the prior art.

, The rack guide means which supports the initial stack of envelopes is pivoted about an axis close to the axis of the oscillating drum so that the leading front edge of the bottom envelope in the stack can be caused to rest in a position most ideal to be picked up by the vacuum suction holes in the oscillating drum.

It may be seen that it is an object of the present invention to provide an improved printing press feeding means. It is another object of the present invention to provide a printing press feeding means which is extremely compact and subject to very little wear. It is still another object of the present invention to provide a feeding means which can be made readily adjustable to many different sizes of envelopes without any change in the basic pickup mechanism. Other objects and advantages will becorne apparent upon consideration of the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of the major moving parts of the present feeder mechanism.

FIG. 2 is a view similar to that used in FIG. 1 but omitting most of the moving parts and showing primarily the rack guide used to carry the stack of envelopes to the feed drum.

FIG. 3 is a sectional view of the apparatus of FIG. 2 taken along line 3-3 in FIG. 2.

FIG. 4 is a sectional view of the floating frames used to carry the transfer rollers of FIG. 1.

FIG. 5 and FIG. 6 show two types of cams that may be used to drive the feed cylinder.

FIG. 7 is a schematic elevational side view showing the relative positions of the major rollers and gears of FIG. 1.

FIG. 7a is an enlarged schematic view of a portion of FIG. 7 showing the action of the stripping fingers.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1 portions of the two main side frames 10 and 12 of the printing press are shown. For simplicity in the drawings the remainder of the printing press is not shown and only the feeding mechanism portion is described. A hollow supporting shaft 14 is carried by frames 10 and 12 and agenerally cylindrical two piece feed drum 16 is carried by shaft 14. A brief reference to the sectional drawing of ,FIG. 3 will demonstrate that hollow shaft 14 is in communication with a series of small holes 17 in cylindrical feed drum 16. A vacuum source 18 is connected to shaft 14 by means of a flexible hose 20 shown only in FIG. 1. In FIG. 3 it may be seen that the cylindrical drum 16 is formed from two pieces which are bolted together so as to afford easy access into the interior of cylinder 16 in order to clean the internal vacuum chamber and maintain free passage of air therethrough. Returning once again to FIG. 1 it may be seen that shaft 14 is actuated at its right hand side by an arm 22 which is connected to another arm 24 which in turn is connected to a bell crank 26 pivoted on a shaft 28. Bell crank 26 is driven in a rocking manner by means of a cam 30. Simultaneous reference should be had to FIG. 7. As cam 30 rotates, a groove 32 therein causes a cam following roller 34 on bell crank 26 to move periodically toward and away from the axis of cam 30. This rocking motion is conveyed by arm 24 and arm 22 to shaft 14'so that cylindrical feed drum 16 rotates back and forth through a small angle. The edge of flat plate 60 is close to drum l6 and two spring stripper fingers and 19 extend up from theunderside of plate 60 and arch into a pair of grooves 21 and 23 on drum l6. Stripper fingers l5 and 19 serve to separate each envelope from drum 16 on the forward stroke and feed it to the transfer rollers62 and 64. Reference to FIG. 7 and 7a will help demonstrate the relative motions involved. In FIG. 7a it can be seen how menvelope 11a passes betweenfeed drum l6 and transfer roller 62 after being picked off the bottom of stack 11.

Spring stripper 19 which is'fastened to plate. 60 by a screw 13 extends up through a notch 60a in plate 60 and'into groove 23 so as to lift envelope 11a from feed drum 16 and onto plate 60.

ly on shaft 14 so as to help feed stock into'the remainder of the printing press. In FIG. 1 the tops of rollers 48 and 50 move toward the topiof the drawing. A' pair of transfer rollers 62 and 64 carried by a shaft 66 are positioned in contact with rollers 48 and 50 and receive rotational motion therefrom. Another I set of transfer rollers 68 and 70 are by a shaft 72 and receive their rotational motion by resting on a driving shaft 74 positioned directly underneath rollers 68 and 70.1 Drive shaft 74'is tumedby a gear 76 which is coupled to the primary drive shaft by a gear 78. Still another set of transfer rollers 80 and 82 are carried by a shaft 84 and rotationally driven by a drive shaft 86 positioned directly under and in contact with rollers 80 and 82.. Drive shaft 86-receives its power from a gear 88 through a gear 90. The three transfer roller shafts 66, 72 and 84 are all carried by floating swing arms which pivot about a single pair of bolts 92 and 94. This swing arm assembly is more easily understood by. a brief reference to FIG. 4.

In FIG. 4 the left hand swing arm assembly for supv. porting the transfer roller shafts is'shown in section,

Transfer roller shaft 66 is carried in a suitable bearing cup in a swing arm member 96 which pivots about a bolt 92..Transfer roller shaft 72 is carried in a bearing cup in a swing arm member 98 also pivoted about bolt spring 102 is positioned between swing arm member 98 and swing arm member 100 above the plane of pivot bolt 92. It may be seen that all of the transfer rollers are free floating and rest against their respective driving elements by virtue of their own weight and the assistance of small springs in the swing arm member assembly. In FIG. 1 it may be seen that rollers 62 and 64 are given an additional downward thrust against rollers I the envelopes are positioned against a pair of brackets 48 and 50 by means of a pair of springs 104 mounted. above swing arm members 96. Springs 104 ac'tagainst' suitable brackets mounted on the frame members 10 1 and 12 which are not shown in FIG. 1.

The remainder of the printing press after transfer rollers and 82 has been omitted exceptfor ablanket I cylinder 106 and an impression cylinder 108. Cylinders 106 and 108 are conventional in nature and comprise a portion of a well known arrangement for printing presses and thus the remainder of the mechanism is omitted from. FIG. 1 for the purposes of clarity.

FIG. 2 and its sectional counterpart, FIG. 3, omit for the most part the driving mechanisms describedwith respect to FIG. 1 and show primarily-the guide rack provided above feed drum 16 which operates to support and deliver a stack of envelopes or other suitable pieces of stock to the feeding mechanism. Referring simultaneously to FIGS. 2 and 3 it may be seen that arectangular three sided frame 114 is pivotedabout-a pair of pivots 115 ,and 117 in frame members 12 and 10, respectively. A pair of risers v116 on frame 114 carry a crossbar ll8so that the entire structure comprising frame 114, risers 116, and cross bar 118 pivots as a unit about pivot pins 115 and 117. The forwardpart of frame 114 is adjustable in height by means of a knob 9 which operates through a cross frame member 8 against the underside of 114. Carried within. this unitary pivoting frame are a pair of L-shap'ed guide members 110 and 112 which are mounted to cross bar 118 by means of a pair of brackets and 132.-.At the front of the feeding means members 110 and 112 rest on frame 114. The side guide rails formed byL-shaped members 1 10 and l 12 may be laterally adjusted by'slid-L ing brackets 130 and 132 along the bar 118 so as to ac-. I

cept a wide variety of stock widths. The rearedges of 120 and 122 which are adjustable fore and aft on members 110 and 112 by means of slots 124 and 126. Theforward edges of the envelopes rest against a pair of alignment guides 134 and 136 which are mounted to cross bar 118 by means of a pair of brackets 138 and 140. A pair of set screws 142 and 144 permit brackets 138 and to be locked to cross bar 118 in a position v such that the lower edges of alignment guides 134 and 136 are positioned so as to square the envelope with respect to rollers 48 and 50 and the other transfer rollers. A vertical separator bar is also mounted on cross bar 118 by means of a vertically adjustable bracket 1.52. Separator 150 is very finely adjustable in height and locked in place by a screw 151 so that its lower tip is the exact distance from feed drum 16 to insure the passage of just one envelopeat a time thus assun'ng separation of the envelopes.

In operation, a stack of envelopes 11 is positioned direction, the envelopes do not move dueto the fact that they are resting against alignment barsIl34 and 136 and separator 150. The stack of envelopes 11 maybe quite high and, if necessary, carried back onto the inclined portion of brackets 120 and 122. Additional side brackets may be mounted on brackets 120 and 122 for lateral positioning although these are not shown in FIG. 2 and FIG. 3. When the vacuum source is activated, oscillating pickup drum 16, on its rearward stroke, sucks the bottom envelope tightly to the drum by means of the air flow through suction holes 17. This action bends the forward or leading edge of the envelope down close to rollers 48 and 50 and feed drum 16 so that the envelope is moved back firmly against brackets 120 and 122. This positioning insuresproper timing and registration of the envelope when it is pulled underneath alignment guides 134 and 136 and separator 150 on the forward stroke of oscillating feed drum 16. The height of separator bar 150 is chosen so that only one envelope at a time may pass between separator bar 150 and drum 16. Since envelopes tend to be thicker on the-flap side than on the nonclosing side, envelopes generally stack in a curving manner. In order to insure that the edges of the envelopes are correctly positioned for selection when stacked in the feed guide means, knob 9 may be turned to raise and lower the front edge of the entire guide mechanism thus inclining the bottom of the stack to the correct angle.

In FIG. 7a and 1, it may be seen that as the envelope 11a is moved forward by suction holes 17 a pair of spring metal fingers and 19 (only finger 19 is visible in FIG. 7a) separate the envelope from drum 16 so as to insert it between transfer rollers-62 and 64 and rollers 48 and 50. At the same time, suction holes 17 move underneath plate 60 thus blocking the vacuum from the envelope. The envelope slides onto the top surface of plate 60 and is urged underneath transfer rollers 68 and 70. The envelope continues to pass between transfer rollers 68 and 70 and shaft 74 across the top surface of plate 60 and between transfer rollers 80 and 82 and drive shaft 86. The envelope is then inserted by transfer rollers 80 and 82 between blanket cylinder 106 and impression cylinder 108. The envelope then continues through the printing press in a manner well known to those skilled in the art. The oscillating pickup drum 16 returns picking up another envelope with each oscillation and feeding the envelope into the series of transfer rollers. It should be noted that as the oscillating pickup drum returns to pick up another envelope and begins to suck on the envelope the return stroke operates to slide the envelope slightly rearward against brackets 120 and 122 thus insuring that the envelope is picked up in the proper position in alignment with the transfer rollers. The cam patterns usable in this machine are shown in FIG. 5 and FIG. 6.

In FIG. 5 one design for cam 30 is shown having a groove 32 therein to engage carn follower 34. The groove reaches a maximum distance from the axis of rotation at point 160. The groove has a minimum position extending from point 162 to point 164 thus givinga rest dwell position of a short predetermined period of time underneath the envelope to insure that the envelope is properly grasped. Since the cylinders used on the present printing press are fairly large they are capable of printing twice on each revolution of the cylinder 106. A second version of cam 30 is shown in FIG. 6 in which a groove 32A has two high and low positions for each revolution, thus, allowing the present feeding mechanism to feed two envelopes in sequence for each revolution of the blanket cylinder 106. Thus, higher speed operation is afforded with a consequent savings in time and expense. In fact, the design of the present press is such as to allow a three-to-one ratio of feeding a generally cylindricalfeed drum disposed in a generally horizontal position having at least one hole therein leading to an intemal vacuum chamber, said feed member adapted to grasp pieces of stock by suction,

a cam means connected to said feed drum adapted to rotationally oscillate said feed drum,

guide means shaped and positioned to direct stock to a position generally corresponding to a first extreme of the oscillatory stroke of said feed drum at which point said feed member cangrasp a piece of stock by suction,

means engaging the leading edge of the stock to strip the stock from said drum during oscillation of the drum toward a second extreme position and releasing said stock from said vacutun hole,

first transfer means adjacent to said feed drum adapted to grasp stock from said feed drum as said drum approaches the second extreme of the oscillatory stroke of said feed drum and direct said stock into a printing press; and

a vacuum source connected to said internal vacuum chamber so as to maintain a vacuum therein during operation of the feeding drum. I

2. The apparatus of claim 1 in which said first transfer means comprises first rollers on each side of said feed means rotating about an axis approximately coincident with the axis of rotation of said feed drum and second rollers disposed near the second extreme of said oscillatory stroke, said stock leaving said feed drum by passing between the first and second rollers and onto a flat surface under which the vacuum supply holes in said feed means pass.

3. The apparatus of claim 2 in which said cam means is connectedvto said feed drum by a hollow shafl along the axis of rotation of said feed drum through which the internal vacuum chamber connects to the vacuum source.

4. The apparatus of claim 3 in which said first rollers rotate about said hollow shaft.

5. The apparatus of claim 4 in which said guide means comprises front, back, and side rail means adjustable to hold a stack of pieces of stock to be printed on top of said feed drum and said first rollers and in which said feed drum moves each piece of stock against the back rails on the rearward oscillation so as to properly register each piece of stock.

6. The apparatus of claim 5 in which said guide means is adapted to be pivoted about an axis parallel to said first roller axis so as to permit the inclination of said stock with respect to said feed drum to be varied so as to compensate for uneven thicknesses of stock.

I 7. The apparatus of claim 6 including second and third transfer roller means disposed next to said first transfer roller means and further including at least one stripper finger riding in a groove in said feed drum to help convey stock to the printing press.

8. The apparatus of claim 7 in which said first, second, and third transfer roller means each' incorporate upper roller sets carried in floating swing arm 

1. A printing press feeding means comprising in combination: a generally cylindrical feed drum disposed in a generally horizontal position having at least one hole therein leading to an internal vacuum chamber, said feed member adapted to grasp pieces of stock by suction, a cam means connected to said feed drum adapted to rotationally oscillate said feed drum, guide means shaped and positioned to direct stock to a position generally corresponding to a first extreme of the oscillatory stroke of said feed drum at which point said feed member can grasp a piece of stock by suction, means engaging the leading edge of the stock to strip the stock from said drum during oscillation of the drum toward a second extreme position and releasing said stock from said vacuum hole, first transfer means adjacent to said feed drum adapted to grasp stock from said feed drum as said drum approaches the second extreme of the oscillatory stroke of said feed drum and direct said stock into a printing press; and a vacuum source connected to said internal vacuum chamber so as to maintain a vacuum therein during operation of the feeding drum.
 2. The apparatus of claim 1 in which said first transfer means comprises first rollers on each side of said feed means rotating about an axis approximately coincident with the axis of rotation of said feed drum and second rollers disposed near the second extreme of said oscillatory stroke, said stock leaving said feed drum by passing between thE first and second rollers and onto a flat surface under which the vacuum supply holes in said feed means pass.
 3. The apparatus of claim 2 in which said cam means is connected to said feed drum by a hollow shaft along the axis of rotation of said feed drum through which the internal vacuum chamber connects to the vacuum source.
 4. The apparatus of claim 3 in which said first rollers rotate about said hollow shaft.
 5. The apparatus of claim 4 in which said guide means comprises front, back, and side rail means adjustable to hold a stack of pieces of stock to be printed on top of said feed drum and said first rollers and in which said feed drum moves each piece of stock against the back rails on the rearward oscillation so as to properly register each piece of stock.
 6. The apparatus of claim 5 in which said guide means is adapted to be pivoted about an axis parallel to said first roller axis so as to permit the inclination of said stock with respect to said feed drum to be varied so as to compensate for uneven thicknesses of stock.
 7. The apparatus of claim 6 including second and third transfer roller means disposed next to said first transfer roller means and further including at least one stripper finger riding in a groove in said feed drum to help convey stock to the printing press.
 8. The apparatus of claim 7 in which said first, second, and third transfer roller means each incorporate upper roller sets carried in floating swing arm frames pivoted at a common point and said second and third transfer roller means have lower roller sets aligned with said upper roller sets carried in the main frame of the printing press.
 9. The apparatus of claim 8 in which said cam means is adapted to oscillate said feed drum twice for each revolution of the cylinders in the printing press. 